1. Field of the Invention
This invention is in the general field of methods and devices for extracting energy from fluids which are expansible, such as steam, hot brines, and the like. The invention is more particularly directed to a method and apparatus by which the fluid is passed, successively, through successive expanders in such manner that one expander removes a portion of the latent energy of the fluid and the next expander removes a successive portion of the energy so as to achieve full utilization of the energy available. The invention is even more particularly directed to a method and means for distributing the load and accommodating for change of capacities due to load and input variations by differential means wherein the increased speed of one expander is compensated for by a decreased speed of another expander so as to work at peak effeciency under the varying conditions of capacity and load.
2. Description of the Prior Art
There have been many attempts at providing successive expansions of working fluids utilizing the principle of extracting latent energy from an expansible fluid, such as double expansion steam engines, and the like. In general certain fixed relationships are involved and the successive expansion arrangements do not necessarily always utilize fully the available energy due to improper balancing of the distribution of power and load. It is inherent in such systems that the multiple expanders are connected to a common shaft in such manner that there is only one fixed condition of input and load during which the successive expanders work most efficiently. In the present invention, due to a differential mechanical coupling of the mechanical output of the expanders, changed input and load conditions are accommodated without loss of efficiency. In this area there is not prior art.